Leaf stripper, more particularly designed for selective vine leaf stripping

ABSTRACT

A leaf stripper which is intended more specifically for stripping vine leaves includes a stripping head which is equipped with a rotary drum with an open-work cylindrical side wall, rotator device for the drum, suction device which can be used to generate a suction air stream that passes through the aforementioned open-work cylindrical side wall of the drum, and a mechanism of channeling the air stream through a portion modifying the side wall. There is a cutting device which is installed close to the side wall portion of the rotating suction drum and which is positioned parallel or essentially parallel to the axis of rotation of the drum. The open-work cylindrical wall of the drum is made from a flexible, deformable material which is permeable to the air stream.

RELATED U.S. APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO MICROFICHE APPENDIX

Not applicable.

FIELD OF THE INVENTION

The invention involves a leaf stripping machine specifically designedfor selective leaf stripping of a vine.

BACKGROUND OF THE INVENTION

Leaf stripping is a technique that consists in eliminating a more orless sizeable quantity of leaves located in the fructiferous zone ofplants. Done manually for a long time in some vineyards, this operation,which aims to improve the quality of the harvest and to make easier themanual work of thinning and picking, is experiencing a growing interestwith the development of mechanical leaf stripping.

The interests in leaf stripping are manifold:

-   -   Promote the aeration of bunches of grapes in order to reduce        rot;    -   Promote thinning in order to improve the coloration (thicker        grape skin);    -   Thin out the vegetation layer in the fructiferous zone for        better penetration and localization of treatments (botrytis;        oidium; gray mold; grape worm; mildew)    -   Improve the maturation of the grapes by a better exposure to the        sun (grapes heavier, flavors more developed and a better        sanitary state of the grape harvest);    -   Promote access to the grapes in order to reduce the time of        labor in manual operations such as thinning (−50%), manual        harvesting (−30% to −40%);    -   Reduce the foliage in order to limit the losses of juice due to        the intake of leaves from the rest of the harvest when it is        done mechanically; and    -   Make drying easier in case of rain by a better exposure to the        sun and a better aeration.

Leaf stripping thus turns out to be an operation that is very much ofinterest and that corresponds well to the problem of optimization oftasks and the pursuit of quality of the harvest.

Several machines and processes have been proposed to date and some ofthem are currently still being used to accomplish this work.

According to a technique for leaf stripping developed by the applicant,in order to accomplish the task, a machine is used that consists of anopen rotary drum, an intake mechanism that makes it possible to generatean intake flow of air that passes from the drum through the lateralcylindrical wall having lateral openings, a mechanism to direct the flowof air through a varying portion of the lateral wall, in a manner so asto catch and pin the leaves against the open lateral wall of the rotarydrum, and a system for leaf stripping that makes it possible to pick offthe leaves pinned against this wall.

For example, in the document FR-2,417,932-A, a device for leaf strippingis described that uses an open rotary cylindrical cage to roll on thevegetation layer and inside of it, a hollow cylinder is housed affixedand equipped with an opening. An aspirator mounted above the insidehollow cylinder makes it possible to create, inside of the insidecylinder, a partial vacuum that has the effect of sucking in the leavesof the vegetation and pinning them against the open rotary cage facingthe opening of the fixed cylinder. Contact rollers mounted onarticulated supports are applied under pressure against the lateralsurface of the cage and are driven in rotation by this surface. Theleaves come to get caught between the turning open drum and the contactrollers, and are torn off of the branches under the force of tractionresulting from the movement of the machine.

A priori, the principle of parting of the foliage by means of an intakeflow of a turbine through an open rotary drum that makes it possible topull and pin the leaves on the lateral surface of the drum appearsclever and economical. It does not appear, however, that the machinedescribed in the document FR-2,417,932 was put on the market, and to theknowledge of the applicant, no stripping machine using this principle isbeing marketed today.

The failure of this machine results certainly from the fact that theprinciple of separating the leaves using frictional contact rollers doesnot appear to be able to be applied concretely for several reasons.

Following the description and the drawings of document FR-2,417,932, thearticulated supports mounted on springs carrying the contact rollers areassigned to be arranged, during work, in the vegetation layer; thisarrangement can not be applied due to the fact that these supports rubin the vegetation layer and hinder the aspiration of the leaves becausethey push back the vegetation; it is not possible to arrange themechanical instruments in the vegetation layer beyond the wall of therotary cage, since they would collide with and be torn off by variousobstacles located in the axis of the vine row, such as stakes, guywires, and above all, poles.

Due to the fact that a relatively sizeable force is necessary in orderto remove the leaves by tearing them off, it is hardly probable that theforce generated by friction of the contact rollers on the drum will besufficient, especially if the leaves or the vine shoots becomepositioned between the wall of the cage and the contact rollers.

This device, as a result of its position relative to the vegetationlayer, and as a result of its principle of separating the leaves bytearing them off, can only cause jamming of the system by accumulationof the plants and damage to the vine.

According to the document FR-2,808,964 A, the applicant has proposed aleaf stripping machine more specifically designed for stripping theleaves of a vine, consisting of at least one leaf stripping head,consisting of an open rotary drum, an aspiration mechanism making itpossible to create an intake air flow going through the lateralcylindrical opened wall of this drum, a mechanism to channel this airflow through a varying portion of the lateral wall, and a cuttingmechanism installed near the portion of the lateral wall of the turningintake drum oriented in parallel or approximately parallel to its axisof rotation, the cutting mechanism is arranged behind a diametral planeof the rotating drum oriented perpendicularly to the direction ofmovement of the machine during work.

This machine represents a first stage of progress to the extent that itmakes it possible to perform leaf stripping with a quality comparable toa trimming of the vegetation layer, taking into account the fact thatthe leaves are cut and not torn, contrary to the solutions previouslyproposed which remove the leaves by tearing them off using blades orknives, or jamming contact rollers.

After separating, the leaves remain pinned against the opened lateralwall of the turning drum and are driven outside the intake field by therotation of this wall. When the portion of the lateral wall covered withcut leaves is isolated from the intake field by the channeling baffle ofthe intake flow, the leaves, no longer subjected to the attraction ofthe air flow, fall due to gravity. This result comprises anotheradvantage, because it eliminates projections of torn leaves likely tocause risks of disease as a result of the particles and dust propelledby blast of the turbine onto the adjacent vine rows.

However, it has been noted that the quantity of the leaves removedremained insufficient to obtain all of the sought-after results, thepartial vacuum generated by the aspirator mechanism does not alwaysexert a strong enough traction action to move the leaves that are onlypinned against the turning drum, in the direction of the cuttingmechanism.

The document WO 01/87047 A describes an evolution of the leaf strippingmachine shown in the document FR-2,808,964 A.

According to this document, the leaf stripping head or each leafstripping head of the leaf stripping machine consists of a tracked guidemechanism comprised of an endless opened belt wound, on the one hand, onthe turning aspirating drum and, on the other hand, on a second drumarranged in front of the aspirating drum, the endless opened belthaving, on the side of the leaf stripping machine assigned to face thevegetation layer, comprised of the vine row, during work, a trajectoryor rectilinear portion, parallel to the path of movement of the leafstripping machine, in a manner so as to have a planar support surface.

The opened tracked mechanism created in this way has the function ofensuring a good guidance and stability of the leaf stripping head on thevegetation layer. It ensures a flexible support of the leaf strippinghead on the vegetation layer, while avoiding crushing the vegetationlayer as a result of its large contact surface.

On the other hand, the cutting mechanism of the machine described in thedocument WO-01/87047 is comprised of a spiral cutting bar consisting of,on the one hand, a cutting screw comprised of a cylindrical rotary shaftequipped with a spiral threading having at least one sharp edge and, onthe other hand, a bed knife comprised of a fixed cylindrical sleeve,open laterally, and inside of which the cutting screw is housed.

It has been observed that the machine constructed in this way tears theleaves to pieces and tears off a non-negligible quantity of young vineshoots.

In summary, though the two versions of the leaf stripping machinesdescribed, respectively, in the document FR-2,808,964 A, and in thedocument WO 01/87047 A have made it possible to simplify the technicalnature of utilization of the equipment, while improving the quality ofthe leaf stripping machine, it has been noted:

-   -   that the adjustment of the intensity of the leaf stripping is        still difficult and depends on the dexterity of the driver of        the machine;    -   that the percentage of leaves cut to pieces or lacerated is not        always negligible; and    -   that the quantity of injuries inflicted on the grape bunches,        especially when the leaf stripping is done late in the season,        still remains an unresolved problem for the wine-growers.

The invention notably has the objective of proposing solutions to theproblems mentioned above.

BRIEF SUMMARY OF THE INVENTION

For this purpose, a leaf stripping machine of the type described in thedocument FR-2,808,964 A has been considered, consisting of a rotatingdrum that has an opened lateral cylindrical wall, mechanisms for drivingthis drum in rotation, an aspirating mechanism that makes it possible togenerate an intake air flow through the opened lateral cylindrical wallof this drum, a mechanism to channel this air flow through a varyingportion of the lateral wall, and a cutting mechanism installed near theportion of the lateral wall of the rotating intake drum and orientedparallel or approximately parallel to the axis of rotation of the drum,this cutting mechanism being arranged behind a diametral plane of therotating drum oriented perpendicularly to the axis of movement of theleaf stripping head of the leaf stripping machine during work.

According to a first characteristic arrangement of the invention, theopened lateral cylindrical wall of the drum is made of a flexiblematerial, whereby this opened flexible and deformable wall is preferablyand advantageously comprised of meshes or interlaced metallic rings ofthe “coat of mail” type.

This flexible and deformable wall makes possible a better adaptation tothe shape of the vegetation layer and to the obstacles present in it,avoids the crushing of the fruits and allows the installation, insidethe drum, of sensor heads and/or stacked sensors that make it possibleto measure the pressure exerted by the drum at different heights of thevegetation layer, in a manner so as to control the instruments ensuringthe good positioning of the drum, relative to the vegetation layer. Inthis way, it is possible to regulate in a very precise manner thepenetration of the drum into the vegetation and to ensure a continuousand perfect following of the vegetation layer.

Due to the fineness of the meshes of the lateral wall of the drum, thesuctioned air is filtered and no remnants are sent into the vine by theaspirator above the machine.

According to another interesting characteristic arrangement of theinvention, a supplementary mechanism for pulling the leaves is arrangedparallel to the cutter bar and set back from it relative to thevegetation during work.

In an advantageous way, this supplementary pulling mechanism can becomprised of a rotating “feeder” coupled to a rotational drive device.

This supplementary pulling mechanism has the advantageous function ofpulling in even more leaves and keeping them pinned against the lateralopened surface of the drum, so that they do not come out again.

Using this device, the leaves pinned against the drum are pulled in thedirection of rotation of the drum and during this movement, the petiolesof the leaves are cut by the cutting bar. Thus, tearing or crumbling ofthe leaves is avoided and as a result, so is the possibility for thepropagation of certain diseases (cryptogamic or others) due to thedispersion of the remnants of the tenderized leaves that have been tornto pieces. This clean cut of the leaves produces a leaf stripping of aquality comparable to that of manual leaf stripping.

According to another important characteristic arrangement of theinvention, the leaf stripping head or each leaf stripping head of theleaf stripping machine is suspended on a carrier chassis constructed andequipped with mechanisms making it possible to spread apart or bringtogether the leaf stripping head(s) of the movement axis of the leafstripping machine, the working position of the leaf stripping head or ofeach of the leaf stripping heads relative to the axis being regulated bya system acting as a function of the deformations undergone by theflexible lateral wall of the drum and resulting from the support of iton the vegetation in the course of work.

In this manner, an excellent monitoring of the profile of the vegetationlayer is obtained, while modulating the force of contact of the drum onthe vegetation layer, in order to not crush the grape bunches due topressure that is too large.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The goals, characteristics and advantages above, and still others, arebest brought out in the description that follows and the attacheddrawings.

FIG. 1 is an elevation view of a first embodiment example of a leafstripping machine according to the invention, shown hitched to the rearof a traditional farm tractor.

FIG. 2 is a top plan view of this leaf stripping machine consisting oftwo symmetrical leaf stripping heads, one of which is shownschematically, the leaf stripping machine being shown in the course ofwork on a vine row.

FIG. 3 is an elevation front view of one of the leaf stripping heads ormodules of the leaf stripping machine shown without its carrier chassis.

FIG. 4 is a top plan view of FIG. 3.

FIG. 5 is a front view of this leaf stripping head.

FIG. 6 is a rear view of this leaf stripping head.

FIG. 7 is an elevation view of the leaf stripping machine consisting oftwo leaf stripping heads or modules arranged on both sides of a vinerow, one of the modules being shown in an axial section.

FIG. 8 is an axial section view of a leaf stripping drum.

FIG. 9 is a section view along the line 9—9 of FIG. 8.

FIG. 10 is a transverse section view of a leaf stripping module.

FIG. 11A is a partial detailed sectional view, in a plane, showing thepositioning of the entire section and the device for driving the drum inrotation.

FIG. 11B is another partial detailed sectional view, in a plane, showinganother embodiment mode of the device for driving the drum in rotation.

FIG. 12 is a longitudinal section view of the mechanisms formotorization ensuring the driving of the rotating drum, the cutting bar,and the rotating feeder.

FIG. 13 is a schematic view of the servo-control of a leaf strippingmodule.

FIG. 14 is a partial detailed plan view showing a sensor housed in therotating drum in order to detect deformations of the flexible lateralwall of the drum when it is moved in rotation on the vegetation of thevine row.

FIG. 15 is a detailed vertical section view showing the deformation ofthe flexible wall of the rotating drum detected by the stacked sensors,during its passage over obstacles (here the grape bunches).

FIG. 16 is a schematic view having a schematic character and in a planeshowing the cylindrical conformation of the lateral wall of the drum ofthe leaf stripping head when it rolls on the vegetation layer withoutencountering any obstacles.

FIG. 17 is a schematic view similar to FIG. 16 and showing thewithdrawal of the lateral support surface of the rotating drum when itencounters an obstacle (grape bunches, for example).

FIG. 18 is a sequential top plan view showing the functioning of theservo system of the leaf stripping modules or heads.

DETAILED DESCRIPTION OF THE INVENTION

Reference is made to the drawings to describe an advantageous embodimentexample, though in no way restrictive, of the leaf stripping machineaccording to the invention.

Though reference is made, in the following portion of the presentdocument, solely to the use of this leaf stripping machine in order tomake a leaf stripping machine specifically for the vine, it is obviousthat such a usage is not restrictive and that this machine can be usedin order to perform leaf stripping of other plants cultivated in theform of aligned shrubs.

This leaf stripping machine is of the type described in the documentFR-2,808,964 A. It consists of at least one leaf stripping head ormodule 1 comprising a rotary aspirating drum 2 consisting of an openedcylindrical wall 3. In a preferred manner, the leaf stripping machineconsists of two leaf stripping heads or modules 1 designed to be placedon both sides of the vegetation of the vine row, during work, in amanner so as to fit tightly around the fructiferous zones, all along itsmovement from one end of the row to the other.

The opened drum has, for example, a height of between 400 mm and 800 mm,according to the leaf stripping models, and a diameter on the order of450 mm.

An aspirating turbine, for example, comprised of a helicoidal vacuumgenerator 4 activated by a hydraulic motor M1, is installed above thedrum 2, in order to create a partial vacuum inside the drum, whichgenerates an intake flow going through the opened lateral wall of thedrum, causing the “gluing” of leaves of vegetation layer on the openedwall or grid of the drum.

Inside the drum 2, affixed and housed near the opened lateral wall 3 ofthe drum, is a mechanism for channeling the flow of air, this mechanismbeing advantageously comprised of a baffle 5, having a shape that isdetermined in order to optimize the efficiency of the aspirating system.This baffle 5 comprises a lateral wall 5 a and a base 5 b by theintermediary of which it is rigidly connected to a lower horizontalelement 6 a of the frame 6 of the leaf stripping head, for example, bymeans of an axle 7 supporting the lower bearing 8 that ensures therotational guidance of the drum 2.

An opening 9 is arranged in the lateral wall 5 a of the baffle. Thisopening extends, for example, over a height that is approximately equalto the height of the opened lateral wall 3 of the rotary drum and has awidth on the order of 220 mm to 260 mm corresponding to an arc on theorder of 70° to 80°.

The major part of the area corresponding to the width of the opening 9is arranged behind a diametral plane P-P of the opened rotary drum 2perpendicular to the axis of movement X-X of the leaf stripping head 1during work, as FIGS. 16 and 17 show.

The opening 9 of the baffle 5 is arranged near the opened cylindricalwall 3 of the rotary drum 2, in a manner so that the baffle ensures, onthe one hand, the waterproofedness over a large part of thecircumference of the opened drum, and, on the other hand, it channels,inside the drum, the air sucked in by the opening 9. It is understoodthat the air sucked in by the turbine 4 is channeled in the form of anintake flow that goes through a varying portion of the rotatingcylindrical wall, the positioning and dimensions of this portion of theopened wall corresponding approximately to those of the opening.

The opening 9 and the portion of the opened wall passing by which is infront of it thus comprise an intake vent arranged in a zone of the drumdesigned to be in contact with the vegetation layer of the vine row.

According to this principle of aspiration of the leaves by directcontact with the vegetation layer, it appears that the partial vacuumflow necessary in order to catch and pin the leaves against the openedcylindrical wall of the drum can be relatively weak relative to the leafstripping machines of other types that stay relatively far from thevegetation layer, which requires a very sizeable partial vacuum, thusmuch power in order to suck in the leaves into the cutting section.

The fixed baffle 5 has, laterally, an approximately cylindrical shape.

In the principle of the rotary contact cage, the intensity of the leafstripping is proportional to the partial vacuum generated by the intake.The volume of the leaves cut can thus be regulated as a function of thevacuum force of the fan. This regulation of the vacuum force can, forexample, be done either by making the speed of rotation of the turbinevary, or by slowing down the air output of the turbine.

The leaves are adhered by the vacuum on the cylindrical grid of therotary drum. Under the combined effect of the pneumatic suction and themechanical rotation of the drum, the leaves are pulled from thevegetation layer. The leaves, lighter than the grapes, also provide alarger surface for suction, in a manner such that a relatively weakpartial vacuum, due to the density difference, is sufficient to “glue”the leaves against the opened lateral surface of the rotary drum,without necessarily attracting the grapes.

A cutting mechanism is installed near the mouth of the suction 9 of therotary drum, in parallel or approximately parallel to the axis ofrotation A-A of it.

The cutting mechanism can be advantageously comprised of an alternatingcutting bar 14 consisting of a mobile blade 14 a and a fixed bed knife14 b, or a linear movement cutting bar, or of any other device.

The cutting bar 14 is oriented in a manner so as to form an angle of±/−45° and, preferably, an angle on the order of 20° with a radius ofthe rotating intake drum 2 passing by the active edge of the cuttingbar. It extends, preferably, over a height corresponding to the heightof the opened lateral portion of the drum that has the vacuum flowpassing through it. A rigid, horizontal shaft in the form of a ski 38 isfixed on the lower part of the structure of the leaf stripping head;this shaft extends in front of the lower end of the cutting bar 14, inorder to protect it, for example in case of an encounter with a verytwisted vine stock.

According to a significant characteristic arrangement of the invention,the lateral wall 3 of the rotary drum 2 is comprised of a flexiblematerial permeable to the air current. This flexible material permeableto the air current can be advantageously comprised of a metallic fabricformed from a multitude of meshes or interlaced metallic rings. Aflexible metallic fabric of this type is generally designated by thename “coat of mail”. The small rings that comprise this metallic fabrichave, for example, a diameter on the order of 4 mm and a thickness onthe order of 5/10 mm.

The upper and lower edges of this flexible opened lateral wall 3 areaffixed to circular upper end elements 10 and circular lower endelements 11, respectively, these end elements being made in a semi-rigiddeformable material such as, for example, rubber, polyurethane, or othersemi-rigid plastic deformable material.

The opened drum thus made is suspended, with a rotational capacity, bythe intermediary of its upper end element 10 and contact rollers 12, onthe case 13 enclosing the intake turbine 4. The upper element 10 of thedrum 2 is, for example, united in rotation with a circular track 10 athat moves over the contact rollers 12 on vertical axles mounted on thecylindrical wall of the case 13, and subjected to the action of elasticpressure mechanisms against the track.

A spring 45 acting by compression and arranged around the vertical axis7 is interposed between the bottom 5 b of the baffle 5 and the lowerguide bearing 8 of the drum 2, comprising an element of the basevertically mobile from it in order to extend the coat of mail 3 in thevertical direction.

The parts 5 c, 5 d of the baffle that define the aspirating mouth of theturning drum 2, rub against the internal surface of the lateral wall 3of the drum. For this purpose, at least the parts 5 c, 5 d of the baffle5 are made of a flexible material.

In an advantageous manner, the baffle 5 can be made of a flexiblematerial, such as, for example, an impermeable cloth affixed to a rigidor semi-rigid frame.

According to another characteristic arrangement of the invention, asupplementary mechanism for pulling leaves is arranged behind thecutting mechanism 14 taking into consideration the direction of movementof the leaf stripping machine, during work, or, more specifically, thereverse direction to the direction of rotation of the turning drum 2 ofthe leaf stripping head of the machine.

In advantageous manner, this supplementary pulling mechanism can becomprised of a rotary feeder 16 tangent to the lateral wall 3 of thedrum 2 and coupled to a rotational drive device, this rotary feederbeing arranged in parallel to the cutting bar 14 and set back from itrelative to the vegetation during work.

This rotary feeder 16 consists, for example, of an axle 16 a, alongwhich vertical flexible blades 16 b are affixed, oriented radially or atan incline from front to back considering the direction of rotation ofthe axle.

It can also be comprised of a rotary brush.

The rotary feeder 16 is arranged next to the cutting bar and it islocated in contact with the flexible side wall 3 of the drum 2, or veryclose to it (the maximum spacing being on the order of 8 mm). The rotaryfeeder 16 and the aspirating drum 2 are driven in rotation in theopposite direction and “downstream”. The leaves pinned on the openedlateral wall of the rotating drum 2 under the action of the partialvacuum created by the turbine 4 are then found to be pinched between thewall and the feeder and pulled towards the rear of the drum. Thepinching combines with the intake vacuum to keep the leaves pinnedagainst the lateral wall of the drum, in order to improve the pulling ofthe leaves, which are detached when their petioles are cut by thecutting bar.

According to an embodiment mode of the invention, a comb 15 can bearranged in parallel and in front of the cutting bar, considering thedirection of the movement of the leaf stripping machine (arrow f1), or,more specifically, the direction opposite the direction of rotation(arrow f2) of the rotating drum, during work (FIG. 16). This comb 15comprises a plurality of stacked horizontal teeth or barrettes, slightlyspaced, the spacing between the teeth being, for example, on the orderof 5 to 15 mm.

Preferably, this comb 15 is replaceable and it is, for example, affixedin a manner so that it can be removed on the fixed bed knife 14 b of thecutting bar.

In this way, it is possible to rapidly mount a comb whose spaces betweenteeth are adapted to the condition of the vegetation, which can be veryvariable as a function of the time of the leaf stripping or the varietyof the grape.

The rotational driving of the drum 2 is done using a vertical rollermotor 17 and a counter-contact roller having a vertical axle 18 or apair of counter-contact rollers 18′ with the parallel vertical axlesmounted with the ability to pivot around a vertical axle, in the mannerof a bogie (FIG. 10). The roller motor 17 is arranged outside the drum 2while the counter-contact roller 18 or the pair of the counter-contactrollers 18′ is placed inside the drum. The flexible opened lateral wall3 of the drum is pinched between the roller motor 17 and thecounter-contact roller 18, or the pair of counter-contact rollers 18′ ina manner so that starting the rotation of the roller motor has theeffect of driving in rotation the drum 2 suspended by means of thecontact rollers 12.

The counter-contact roller 18 or the pair of counter-contact rollers 18′is subjected to the action of elastic pushing mechanisms 37 which holdit permanently under pressure against the internal surface of theflexible lateral wall 3 of the drum which is thus found to be heldconstantly applied against the drive roller 17.

A flexible vertical flap 39 affixed to a rigid vertical element 40 ofthe frame of the leaf stripping head can be arranged behind the pullingroller 16, in order to prevent the cut leaves or vine shoots from beingable to be taken between the roller motor 17 and the lateral wall 3 ofthe drum 2.

A common motorization makes possible:

-   -   the driving in rotation of the rotating drum 2;    -   the operation of the cutting bar 14; and    -   the driving in rotation of the feeder 16.

This common motorization consists of, for example, a hydraulic motor M2whose output shaft 19 is coupled to the vertical shaft 20 of aneccentric 21 whose connecting rod 22 is coupled, by the intermediary ofa ball joint 23 and a link 24 to the upper end of the blade 14 a of thecutting bar 14. In this way, the starting of the rotation of the shaft20 of the eccentric 21 ensures an alternating longitudinal movement ofthe blade 14 a of the cutting bar.

The lower end of the vertical shaft 20 of the eccentric is connected,for example, by the intermediary of a coupling shaft 25, to the upperend of the axle 16 a of the rotary feeder 16. It is understood thatstarting the rotation of the shaft 20 of the eccentric 21 also ensuresthe rotation of the feeder 16 arranged in the axial extension of theshaft.

The motorization consists of another vertical shaft 26 arranged at adistance from the vertical coupling shaft 25 and connected to this shaftby a transmission, comprised of, for example, a flexible strap woundaround the wheels set on these shafts 25, 26, respectively. Preferably,this transmission comprises a belt 27 wound, on the one hand, on apulley 28 set on the coupling shaft 25, and, on the other hand, on apulley 29 set on the shaft 26 whose lower end is coupled to the upperend of the vertical axle 17 a of the drive roller 17. The receivingpulley 29 has a diameter approximately equal to or slightly greater thanthat of the driving pulley 28, in a manner so that when the shaft 25 isset into rotation, the shaft 26 is driven in rotation at a speedapproximately equal to or slightly slower than that of the shaft 25.

In other words, the tangential speed of the rotating feeder 16 is atleast equal to the tangential speed of the drum 2, or slightly greaterthan that of the drum.

On the other hand, the rotational speed of the drum 2 is equal to orapproximately equal to the speed of movement of the leaf strippingmachine during work. If you consider that the drum(s) 2 of the leafstripper roll(s) over the vegetation V, an immobile contact of thedrum(s) relative to the vegetation results at a time T. Thus, there isno friction between the leaf stripper, the bunches of grapes and thelateral wall 3 of the drums.

The motorization described above is housed in a case 30 affixed,laterally, to an upper element 6 b of the framework of the leafstripping head. The vertical shafts 20 and 26 are mounted so as torotate in the bearings 31 and 32, respectively, installed in the case30.

According to another characteristic arrangement of the invention, theleaf stripping head comprises a servo system that enables, at its leafstripping head 1 or at each of its leaf stripping heads or modules 1, tofollow the profile of the vegetation layer while regulating the contactforce of the drum(s) 2 on the vegetation layer, in order to not crushthe grape bunches. In the case of a leaf stripper equipped with twosymmetrical leaf stripping heads, each leaf stripping head is controlledindependently of the other one.

The servo control consists of at least one sensor 33 housed inside therotating drum 2, near the flexible opened lateral wall 3 of the drum. Inan advantageous manner, several stacked sensors are positioned insidethe rotating drum 2, preferably at an equal distance from each other,the extreme sensors (upper and lower) of this vertical alignment beingarranged at a distance from the upper and lower edges, respectively ofthe opened lateral wall 3.

The sensors 33 can be advantageously comprised of sensors using the Halleffect installed affixed and coupled to the stacked sensors 42A, 42B,42C,42D, . . . placed in contact with the flexible opened lateral wall 3of the drum 2.

Each sensor 42 is, for example, comprised of a contact shaft with acurved shape supporting a magnet that acts together with the Hall effectsensor 33 to which this sensor is connected, in a manner so that themovements of this sensor 42 are detected and measured by the sensor 33.

As a result, the sensors 33 make it possible to detect and measure thedeformations of the flexible lateral wall of the drum, resulting fromthe encounter of obstacles or an abnormal pressure of the leaf strippingdrum on the vegetation. They make it possible to activate theelectromechanical instruments or other instruments that control thepositioning of the leaf stripping drum relative to the vegetation orvegetation layer V, and, as a result, to correct the position of thedrum and ensure a continuous following of the vegetation layer.

The flexibility of the lateral wall 3 makes it possible to press on eachsensor 42A, 42B, 42C, 42D, . . . , over a distance on the order of 60mm.

The leaf stripping head or each leaf stripping head 1 of the leafstripper is carried by a frame 36, making it possible to mount it behind(FIGS. 1 and 2) or in front of a farm tractor. It is suspended in apendulum-like manner, for example, by means of an articulation by ahorizontal axle 46, connecting a vertical element of its frame 6 to avertical element of the frame 36 (FIG. 3).

This carrier chassis 36 is (in a manner that is itself known from theprior art) constructed and equipped with mechanisms that make itpossible:

-   -   to move apart or move together the leaf stripping head or each        leaf stripping head 1, relative to the movement axis Y-Y of the        leaf stripper, the mechanisms advantageously comprising a        deformable suspension parallelogram 36 a made by an upper part        of the chassis; and    -   to regulate the position of the leaf stripping drum(s) 2        relative to the vertical; these movements being controlled by        the servo system as a function of the information transmitted by        the sensors 33.

The servo system consists of another activator 41, for example,comprised of an electric jack provided with an electronic board 43 formanagement of the servo control using an algorithm that makes itpossible to determine successive deformations of the flexible lateralwall of the drum as a function of the instructions sent by the sensors33. A potentiometer 44 makes it possible to adjust this information inorder to regulate the pressure of the leaf stripping module on thevegetation.

The electronic board 43 sends the information to the activator 41 whichacts on the deformable parallelogram 36 a on which the leaf strippinghead 1 is suspended, or each leaf stripping head (1), in a manner so asto obtain an optimum position of the leaf stripping drums 2 relative tothe vegetation during work. A potentiometer 45 coupled to the main axisof the parallelogram limits the minimum and maximum distance of thejack.

According to this servo system, an intermediate pushed-back position ofthe sensors is defined to correspond, for example, to a pushed-inposition on the order of 20 mm and at this position, the leaf strippinghead maintains a stable position; a more sizeable pushed-in position ofthe sensors drives a pulling back of the leaf stripping head, while therelaxation of pressure on the sensors drives the movement of the leafstripping head and its application against the vegetation layer.

The sequential representation of FIG. 18 shows this functioning. On theleft of the drawing, the pressure of the vegetation against the lateralwall of the drum 2 of the leaf stripping head 1 is normal, the sensorsare moderately pushed-in, the position of the leaf stripping head isstable. In the center of the drawing, the vegetation layer has apro-eminent part, the pressure of the vegetation against the lateralwall of the drum is more sizeable, the sensors 42 are very pushed-in,and activate the sensors 33 that send the information to the electronicboard 43, the leaf stripping head 1 moves back. On the right of thedrawing, the vegetation is not in contact with the drum 2 of the leafstripping head 1, the sensors are relaxed, the leaf stripping head comesto press against the vegetation. When there is a hole in the vegetation,the sensors 42 are totally decompressed and the leaf stripping head getscloser to the axis of the vine row.

In an advantageous and known manner (WO-01/87047A), a cutting bar 34 orother cutting mechanism such as an alternating cutting bar can bearranged vertically in front of the rotary drum of the leaf strippinghead or each leaf stripping head. This cutting bar 34 activated by ahydraulic motor M3 is carried by an element 35 of the leaf strippingmachine chassis and is arranged at a sufficient distance from the leafstripping drum 2, in a manner so that the cutting fragments do notdisturb the work of the leaf stripper.

When the leaf stripper comprises two leaf stripping heads, they arearranged on both sides of the vine row and can move in a manner to moreor less fit tightly around the row and also to open and re-close at theinput and output of the row, respectively. Leaf stripping is thuspossible on the two sides of the row, or, alternatively, on one or theother sides. During leaf stripping on only one side, the drum that islocated on the other side of the paling can continue to roll over thevegetation, which makes it possible for the paling to be held betweentwo drums and to not be pushed from one side or the other. The absenceof leaf stripping action on the side where this action is not desired isobtained by stopping the intake vacuum of the inactive leaf strippinghead.

The leaf stripper according to the invention can be easily installed onan inter-row tractor, or on a spanning tractor, or on a multi-functiontool holder. It can also be self-propelled.

1. An apparatus for selective leaf stripping of a vine, the apparatuscomprising: at least one stripping head having a drum, said drum havinga cylindrical side wall; a means for rotating said drum about agenerally vertical axis, said means for rotating cooperative with thestripping head; an aspirating means positioned on the stripping head forflowing air through said cylindrical side wall of said drum; achanneling means cooperative with said drum for channeling the air flowthrough a varying portion of said side wall of said drum; and a cuttingmeans positioned adjacent to said side wall of said drum, said cuttingmeans for stripping leaves, said cutting means extending in generallyparallel relation to said vertical axis about which said drum rotates,said cylindrical side wall being formed of a flexible and deformablematerial that is permeable so as to allow the air flow to passtherethrough.
 2. The apparatus of claim 1, said flexible and deformablematerial of said cylindrical side wall being of a metallic fabricmaterial.
 3. The apparatus of claim 1, further comprising: a vehiclehaving the stripping head thereon, said vehicle having a speed ofmovement during operation, said drum being rotated by said means forrotating so as to have a tangential rotational speed at least equal tosaid speed of movement.
 4. The apparatus of claim 1, said drum having acircular upper end and a circular lower end, said cylindrical side wallbeing affixed to said upper and lower ends.
 5. The apparatus of claim 4,said circular upper end suspending said cylindrical side wall therefrom.6. The apparatus of claim 1, further comprising: a tensioning meansconnected to said cylindrical side wall for tensioning said side wallvertically.
 7. The apparatus of claim 6, said drum having a lower axleof rotation, said tensioning means comprising: a spring extending aroundsaid lower axle of rotation so as to act in compression against a lowerpart of said drum.
 8. The apparatus of claim 1, further comprising: aleaf pulling means arranged parallel to said vertical axis, said leafpulling means for pulling on leaves passing thereinto, said leaf pullingmeans positioned adjacent to said cutting means.
 9. The apparatus ofclaim 8, said leaf pulling means comprising a rotating feeder coupled toa rotating guide.
 10. The apparatus of claim 8, said leaf pulling meanspositioned adjacent to said cylindrical side wall of said drum.
 11. Theapparatus of claim 9, said rotating feeder comprising: an axle havingflexible vertical blades affixed thereto and extending therefrom. 12.The apparatus of claim 9, said rotating feeder comprising a brush. 13.The apparatus of claim 9, said drum rotated at a tangential speed, saidrotating feeder having a tangential speed at least equal to thetangential speed of said drum.
 14. The apparatus of claim 1, furthercomprising: a comb arranged in parallel to and in front of said cuttingmeans.
 15. The apparatus of claim 1, said cutting means positionedbehind a diametrical plane of said drum and oriented perpendicular to adesired movement axis of the stripping head.
 16. The apparatus of claim1, said channeling means comprising a plurality of vertical portionsdefining an aspirating opening for said means for aspirating, saidplurality of vertical portions positioned adjacent an internal surfaceof said cylindrical side wall of said drum, said plurality of verticalportions being formed of a flexible impermeable material.
 17. Theapparatus of claim 16, said channeling means comprising an impermeablecloth affixed over said plurality of vertical portions.
 18. Theapparatus of claim 1, said cutting means comprising a vertical cuttingbar oriented at a 45° angle with a radius of said drum extending to acutting edge of said cutting bar.
 19. The apparatus of claim 1, saidmeans for rotating comprising: a vertical roller motor positionedoutside said drum; and at least one vertical counter-contact rollerpositioned within said drum, said cylindrical side wall of said drumbeing pinched between said vertical roller motor and the counter-contactroller.
 20. The apparatus of claim 1, said means for rotatingcomprising: a vertical roller motor positioned outside said drum; and apair of counter-contact rollers having parallel axes, said pair ofcounter-contact rollers positioned within said drum and pivotable arounda vertical axle, said cylindrical side wall of said drum being pinchedbetween said vertical roller motor and said pair of counter-contactroller.
 21. The apparatus of claim 19, said means for rotating furthercomprising: a common motor drivingly connected to said drum.
 22. Theapparatus of claim 21, said common motor being a hydraulic motordrivingly connected to a eccentric having a connecting rod coupled to anupper end of said cutting means.
 23. The apparatus of claim 19, said atleast one counter-contact roller being urged by an elastic pushingmechanism so as to be maintained under pressure against an internalsurface of said cylindrical side wall.
 24. The apparatus of claim 1, thestripping head being suspended on a carrier chassis which is movablealong a movement axis, the apparatus further comprising: a servocontrolling means cooperative with said carrier chassis for moving saidstripping head along said movement axis as a function of deformations ofsaid cylindrical side wall.
 25. The apparatus of claim 24, said servocontrolling means comprising: a means for detecting the deformationshoused within said drum.
 26. The apparatus of claim 25, said means fordetecting comprising: at least one sensor housed within said drumadjacent said cylindrical side wall.
 27. The apparatus of claim 26, saidat least one sensor comprising: a plurality of sensors positioned invertical alignment and spaced from each other within said drum.
 28. Theapparatus of claim 26, said at least one sensor comprising a contactshaft in contact with said cylindrical side wall.
 29. The apparatus ofclaim 24, said servo controlling means comprising: an electrical jackhaving an electronic board suitable for servo control by using analgorithm to determine successive deformations of said cylindrical sidewall of said drum, said servo controlling means for acting on adeformable parallelogram on which the stripping head is suspended so asto set an optimum position of said drum.